Telephone



(No Model.)

A. P. CONGDON.

TELEPHONE.

No. 303,809. Patented Aug. 19, 1884.

FGZ

Flai.

IINTTED STATES PATeNT Trice.

ALBERT' F. CONGDON, OF PHILADELPHIA, ASSIGNOR T() VILLIAM KENNY- SON, OF NORRISTOVN, PENNSYLVANIA.

TELEPHONE.

SPECIFICATION forming part of Letters Patent No. 303,809, dated August; 19, 1884,

Application tiled March 5, 1884. (No model.)

To (tu wiz/ont TL may concern.:

e it known. that I, ALBERT F. CoNGDoN, ol' Philadelphia, Pennsylvania, have invented certain Improvements in Telephones, of which the following is a speeilieation.

My invention consists of an improved construction el"reeeivingtelephone, as more fully described hereinafter.

In the accompanying drawings, Figure 1 is a vertical section through the ease of my improved. telephonie receiver. Fig. 2 is avertcal section ofthe instrument at right angles to that of Fig. l, and Fig. 3 is a section on the line l 2.

A is the iuelosing-case, which may be of any desired shape, and provided with the usual perforated screw cap, A', forming the earpiece and inclosing the diaphragm B.

The electro-magnet E is of the horseshoe type, the two polar extremities c e being surrounded bythe same coil D. Between the two legs of the horseshoe. behind the coil D, I wind longitudinally a coil, F, over transverse pinsfj", the two coils being in the same circuit and having their terminals connected to the usual binding-posts, j) p.

The pin j', I prefer to make of some noir magnetic material; but the pin f is magnetic, or has a magnetic ferrule forming the bend of the horseshoe, which, as usual, is a permanent magnet as well as an electro-magnet. The connecting-piece g, into which passes the re4 taining-screw y', Vforms part of the permanent magnet, while the spacingblock h may or may not be of magnetic material, as desired. A

telephonie receiver.constructed as described, an d provided with the coil F,wonn d round the bend of the horseshoe and along the legs, I have found to be much more efiicient and to give better results than without the coil. deed, I have obtained satisfactory results in reproducing speech with the coil F only in eircuit, the coil D being removed; but the use of the two combined is the best.

I claim as my inventionl. The combination of the case and diaphragm of a reeeiving-telephone with a horseshoe-magnet having a coil wound over the bend and longitudinally of the legs of the horseshoe, substantially as set forth.

2. The combination of the ease and dia`- phragm of a receiving-telephone with a horseshoe-magnet having one coil around its polar extremities and another wound over the bend and longitudinally of the legs of the horseshoe, 55

substantially as described.

3. rEhe combination of the ease and diaphragm of a receiving-telephone with a horseshoe-magnet having one coil wound around its polar extremities and another wound over the 6o 

